Magnesium base alloy



total added metals, but where the alloy is to be used for the production of wrought shapes generally, suitable compositions are those containing more than 90 per cent of magnesium and less than 10 per cent of total added metals. For the production of castings, the alloy should preferably contain to 92 per cent of magnesium and the various alloying ingredients in the following proportions: 4 to 10 per cent of aluminum, 2 to 8 per cent of cadmium, 1 to 6 per cent of lead, 1 to 6 per cent of tin, and 1 to 4 per cent of zinc. For the production of wrought shapes by extrusion and forging, the alloy should preferably contain to 96 per cent of magnesium and the various alloying ingredients in the following proportions: 1 to 8 per cent of aluminum, 1 to 3 per cent of cadmium, 0.5 to 2 per cent of lead, 0.5 to 3 per cent of tin, and 0.5 to 2 per cent of zinc. If the alloy is to be fabricated by rolling rather than by extrusion or forging, the percentage of aluminum should preferably lie within the range of 1 to 5 per cent. 1

Mynew polynary alloys may be prepared by the methods usually employed for melting and alloying metals with magnesium, such as adding the respective alloying metals singly or jointly to a bathof molten magnesium protected from oxidation by a cover of fluid flux. -The solution heat treatment for the zinc-free alloys may consist in heating the material for 20 hours at 430 C., followed by air cooling, or, when zinc is present in the alloy, 12 hours at 320 0. plus 16 hours at 420 C., followed by air cooling. The aging treatment consists of approximately 16 hours heating at C., subsequent to the above solution heat treatment. Plastic deformation operations, such as extruding, forging, and rolling are best conducted at temperatures between 300 and 400 C.

Other modes of applying the principle of my invention may be employed instead of those explained, change being made as regards the ingredients and the steps herein disclosed, provided those stated by any of the following claims or their equivalent be employed.

I particularly point out and distinctly claim as my invention:-

1. A magnesium-base alloy containing from approximately 1 to 12 per cent of aluminum, and from about 1 to 10 per cent of cadmium, and from about 0.5 to 10 per cent of lead, the balance being magnesium.

2. A magnesium-base alloy consisting of from about 4 to 10 per cent of aluminum, and from about 2 to 8 per cent of cadmium, and from about 1 to 6 per cent of lead, the balance being magnesium.

3.'A magnesium-base alloy consisting of from about 1 to 8 per cent of aluminum, and from about 1 to 3 per cent of cadmium, and from about 0.5 to 2 per cent of lead, and from about 90 to 96 per cent of magnesium.

4. A magnesium-base alloy consisting of about 4 per cent of aluminum, and of about 4 per cent of cadmium, and of about 2 per cent of lead, the balance being magnesium. 

